Brake cylinder



FIG. 1 is a front, bottom, left side perspective view of a brake cylinder showing the new design;

FIG. 2 is a top perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a rear elevational view thereof; and,

FIG. 6 is a rear, bottom, left side perspective view thereof.

The portions of the structure depicted in broken lines form no part of the claimed design. 

The ornamental design for a brake cylinder, as shown. 